The Applicant has previously described a method of enabling users to access information from a computer system via a printed substrate e.g. paper. The substrate has coded data printed thereon, which is read by an optical sensing device when the user interacts with the substrate using the sensing device. A computer receives interaction data from the sensing device and uses this data to determine what action is being requested by the user. For example, a user may select a printed hyperlink using a sensing device and retrieve a corresponding webpage via a display device or printer.                It would be desirable to enhance the functionality of the above-described system. Enhanced functionality would encourage greater use of the system and, hence, generate increased revenue streams for system providers.        More particularly, it would be desirable to provide users with useful information from every interaction with the substrate, irrespective of whether the user has interacted with a specific interactive element (e.g. hyperlink) on the substrate.        It would further be desirable to provide users with greater control over what type of information they receive when interacting with a printed substrate.        